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Hate, tangled messes of cables? Sick of always having to stay close to an outlet?

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Well, there's actually a way to power certain devices without having an outlet anywhere nearby.

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And I'm not talking about a battery. I'm talking about power over Ethernet, or PoE,

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not to be confused with the Raven guy. The basic idea is simple.

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A single Ethernet cord carries both power and data,

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allowing you to say, never more to a separate power cable.

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How's it going, PoE? Oh, PoE? Ah, and you don't even need any special Ethernet cable.

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Most of us use CAT 5E or CAT 6 these days for internet,

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and either one of these will work just fine. But unfortunately, you can't just connect any two gadgets

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with an Ethernet port and expect power delivery. The client device and the router or switch

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you're connecting it to both have to support PoE.

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The good news here, though, is that PoE switches typically don't cost that much more than regular ones.

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But what kinds of things really benefit from having PoE to begin with?

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One big one is wireless access points. You can often get better Wi-Fi performance

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by using a standalone access point, instead of the one built into your off-the-shelf router,

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and many of these access points support power over Ethernet.

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This can be useful at home, but it's especially common in larger commercial

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or high-density environments that need multiple access points across far-flung distances

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where it would be impractical to run both Ethernet and power cables.

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There are also PoE clocks available in both analog and digital.

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A single Ethernet cable both provides power and connects the clock to an internet time server

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so you'll never have to worry about setting the clock or changing the battery.

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And yet more applications include VoIP, where one Ethernet cable going to your desk phone

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gives you voice capabilities and power. Intercoms, smart door locks, and surveillance cameras

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can all also use PoE. Basically anything that needs a constant data connection

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but doesn't have massive power requirements can benefit.

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So you can send data and power on the same cable because the Ethernet protocol moves data

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using something called differential signaling.

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Basically two signals are sent that have the same voltage,

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but one is positive and one is negative. The orientation of the positive and negative signals

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determine if the bit is a one or a zero. Power over Ethernet just applies a larger voltage

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to the wiring inside the Ethernet cable. It doesn't affect the positive negative difference

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of each bit, so data transmission is unimpeded.

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But speaking of larger voltages, just how much power can PoE deliver?

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Well, there are actually a few different versions of the standard that deliver different wattages,

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which we've summarized here on this chart. Those higher wattage versions are useful

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for devices like high powered wireless access points or rotating cameras that need the extra wattage

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to turn a motor. So yeah, all this sounds pretty cool,

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but before you rush out to buy a bunch of PoE enabled stuff like their Pokemon cards, keep this caveat in mind.

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Many PoE devices don't even have a regular power port

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and so can only be powered via PoE. And if you don't have a switch or router with a PoE port,

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you'll need to pick up something called a PoE injector.

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And don't worry, this isn't some kind of weird cyber syringe.

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Rather, it's a little wall wart that plugs into a standard outlet,

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but also features a pair of Ethernet ports. One connects to the client and the other

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to your router or switch. Just make sure the standard supported by the injector

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is at least the same as what your client device needs to ensure it gets adequate power.

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You can even combine an injector with a PoE splitter

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and power a non-PoE client as well.

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Also remember that PoE has a maximum range of 100 meters without a repeater.

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And while that's a fairly long way, you can eat through that fast

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if your cable run has lots of twists and turns. Speaking of twists, that's the end of this episode.

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Ha, I bet you didn't see that coming. Guys, thanks for watching the video.

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Like it if you liked it, dislike it if you disliked it. Check out our other videos.

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Comment below with video suggestions and don't forget to subscribe to TechWiki

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and follow TechWiki. We're making these actually all the time.

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